Demographics & People — Buffalo, Illinois
Population Overview
| Population (Census) | 405 |
| Estimated 2026 | ~700 |
| Median Age | 45.9 |
| Total Households | 171 |
| Family Households | 111 |
| Average Household Size | 2.37 |
| Diversity Index | 0.0433 (relatively homogeneous) |
Race & Ethnicity
| White | 355 |
| Black or African American | 0 |
| Asian | 2 |
| Hispanic or Latino | 6 |
Heritage & Ancestry
| Group | Count |
| Unclassified or not reported | 109 |
| German | 98 |
| English | 92 |
| Other groups | 69 |
| Irish | 63 |
| American | 35 |
| Norwegian | 26 |
| French (except Basque) | 15 |
| Hispanic: Mexican | 8 |
| Hispanic: Hispanic or Latino | 8 |
Language
| English Only | 388 |
| Spanish | 6 |
| Population 5+ | 398 |
Veterans
| Veterans | 31 |
| Population 18+ | 312 |
Source: Census ACS 5-Year 2023; Census ACS 5-Year 2023, Table B01003; Census ACS 5-Year 2023, B19013. Data for Buffalo, Illinois.